I'd say you definitely have a memory leak Ram is supposed to be dynamic, software borrows a little, uses it and when done, returns it to the memory available pool. A leak is when the software is done, but for some reason the allocated ram is not returned to usable status.
The hardest part about dealing with a memory leak is finding it, especially in Windows 10 as there are simply So many drivers, services, processes starting, stopping at any given time. So your best bet is to try killing it on accident. Make sure ALL 3rd party software, Windows, motherboard chipset drivers (Lan, audio, Sata, pcie, USB family etc), gpu drivers is the latest possible, that includes your AV and malwarebytes. I'd also download and use ccleaner from piriform.com, run that default several times and also use the registry cleaner (say Yes! to backups) several times as temp files and orphans can also screw up memory allocation in dead ends.